She's grown since they last time met and is now quite the young lady.
So much so that 12-year-old cancer patient Alice Marples looked shy if delighted to meet Prince William at a new children's unit to treat the disease in London.
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The caring royal has been following her progress ever since she interviewed him in March 2009 for CBBC show Newsround.
In a few days, brave Alice will fly to the US for pioneering radiotherapy on the brain tumour she has been fighting for eight years.
But before that there was time for one exciting treat – presenting a bouquet to the Prince's new wife.
Before the couple's engagement at the Royal Marsden Hospital, Alice told the Standard she was overjoyed to be meeting the Duchess and "having a catch-up" with William.
"I'm really excited. He was so lovely, and it will be lovely to see him again and meet his wife," she said, adding: "I watched the royal wedding and it was amazing. I thought Catherine's dress was beautiful."
The future King – who has supported the Royal Marsden as president – had just come off a 24-hour shift at his search and rescue unit in Angelesy.
Nevertheless, he made an effort to look upbeat as the couple talked to several young patients, rolling up his shirt sleeves for a more casual look.
One of those he met was seven-year-old Ellis Andrews, who is awaiting a bone marrow transplant.
Meanwhile, the Duchess of Cambridge chatted to Fabian Bate, nine, who was in the middle of four hours of chemotherapy to treat leukaemia for the second time.
His mother said: "Kate asked loads of question and said she was sorry the treatment hadn't worked first time round."
The couple also shared a joke with another leukaemia sufferer Digby Davidson, after hopping on to his bed.
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